birdnerd

So I just picked up a 94 Jeep Grand Cherokee, 4.0 liter I6, Auto. Everything seemed fine on the test drive so I bought it. But on my way home (about 60 miles) I realized that I was revving really high, 3k at 60mph. I backed out the throttle and it seemed like my transmission disappeared. It would just rev but not go. The light for the overdrive off is lit up but pressing the button won't switch it off. This is the first auto jeep I have ever had any help would be much appreciated.

Bustedback

I think the OD switch light will come on when there is a transmission code set. The first thing to check would be the fluid level. I'm not sure if cycling the ignition key off and on three times will flash transmission codes on a 94 or not. The best thing to do would be to have a transmission shop check it out, throwing parts at it will be more expensive in the long run.

black4.0lgrndcherlerado

hey man i had similar issues with my jeep iv owned it for over 2 years did all services when due kept up on tranny services but about 4 months ago drivin 60 running just fine then it reved to 3k rpms and backed off the throttle went to hit it to see if it would kick down it wouldnt, put it in and out of nuetral and only reving no moving, then coasting till i hit about 20mph then dies, wont start somehow i lost power in my hot wire to my fuel pump?? any ideas how that could happen?? its not a relay.. and now it randomely kicks in and out of overdrive more and more every day could be my tranny going out but for some reason it keeps showing a tps code? iv replaced it 4 times lol but i hear the 42re trannys arnt very great lol any thoughts or ideas would be greatly appritiated thanks!!

birdnerd

So I'm getting a code 12 out of the transmission. It is the transmission output speed sensor. Located in the transmission not the transfer case. I'm going to swap the sensor tomorrow. I will let you know if it fixes it.
It has also started to give off a low hum/rumble when I let off the gas at speed. Not really sure what that is bit I know the cv shafts ore shot. It will get you any info once I discover something.